The present disclosure relates to an image processing apparatus and method, an image processing system and a program. Specifically, the present disclosure relates to an image processing apparatus and method, image processing system and program that can easily realize calibration of multiple cameras, which photograph stereo images, at high accuracy in a small space.
In general, a technique that can photograph a three-dimensional image by the use of multiple cameras is common.
As a method of generating a three-dimensional image, there is known a general method of forming a stereo camera by setting up cameras of two different viewpoints, calculating the disparity based on images photographed by the cameras of two different viewpoints which configure the stereo camera and generating a three-dimensional image by the use of this disparity.
By the way, although it is premised that the cameras of two different viewpoints used herein is set up in an appropriate direction, it is known that a certain physical gap is generated no matter how they are set up. Therefore, generally, by taking images formed with a chart pattern with respect to respective imaging directions of the cameras of two viewpoints and calculating correction parameters by calibration in advance using the imaging results, actual imaging results are corrected by these correction parameters and used.
Various techniques to execute this calibration have been suggested so far, and, for example, it is suggested as a first method that four points of the same distance on the plane are photographed by cameras of two viewpoints to calculate a correction parameter from the photographed results (see JP 2011-253376A).
Moreover, as a second method, Patent Literature 1 suggests that a surface with different depths provided by making a hole in a chart pattern is photographed as one image and calibration processing is performed by one image to calculate a correction parameter.
Further, for example, it is suggested that a correction parameter is calculated by printing a calibration pattern on a transparent chart, arranging this in different distances, photographing these images and executing calibration processing by the use of the photographed results (see JP 2006-250889A).